Fabrication of electronic circuit elements using liquid deposition techniques is of profound interest as such techniques provide potentially low-cost alternatives to conventional mainstream amorphous silicon technologies for electronic applications such as thin film transistors (TFTs), light-emitting diodes (LEDs), RFID tags, photovoltaics, and the like.
Solution-processable conductors are of great interest for use in such electronic applications. Metal nanoparticle-based inks represent a promising class of materials for printed electronics. However, most conventional printing methods such as inkjet printing, screen printing and flexography printing cannot offer very high-resolution features. For example, screen printing normally results in line having a width of 100 microns, while inkjet printing with a 10 pL nozzle usually forms a line having a width no less than 30 microns. Although special inkjet printers may be designed to print very small droplets, it is very difficult to achieve reliable and consistent printing results, particularly using particle-based ink, since the nozzle trends clog. Although conventional photolithography method can produce high-resolution lines, such as 1 to 5 microns, this method is too costly for low-cost electronic fabrication.
While currently available methods for preparing conductive elements for electronic devices are suitable for their intended purposes, to achieve high-resolution devices, there remains a need for a low-cost method suitable for preparing conductive structures using stable metal ink compositions, the conductive features having a width of less than 10 microns which is comparable with conventional lithographic method.